Indicating control knob



y 1949 A. A. SEASONGOOD 2,470,582

INDICATING CONTROL KNOB I Filed March 14, 1947 2 Sheets-Sheet l //v VEN TO P /4A 55 T A 55450A/a000 A TTOPNEVS May 17, 1949.

Filed March 14, 1947 A.A.SEASONGOOD INDICATING CONTROL KNOB 2 Sheets-Sheet 2 AM 34 a /4 Tiq-5- INVENTOR 445227 4 55450/V6000 ATTORNEYS Patented May 17, 1949 INDICATING CONTROL KNOB Albert A. Seasongood, Melrose Park, Pa., assignor to Leeds and Northrup Company, Philadelphia, Pa., a corporation of Pennsylvania Application March 14, 1947, Serial No. 734,808

4 Claims. 1

This invention relates to control knobs for multi-position switches, valves and the like, and particularly to control knobs having associated indicia identifying its various control settings.

In accordance with th invention, the control knob is provided with an internal dial member having position-indicating characters or markings successively individually visible through a window or aperture in the knob as it is rotated to its various control settings. Though requiring less panel space than the usual control knob constructions having external dials and pointers, there is no loss of readability. Moreover, as only one symbol or group of symbols is visible at any one time, there can be no uncertainty of the knob setting.

More particularly, the numerals, letters or other symbols or indicia are arranged on the surface of a cone-shaped dial member so mounted for rotation, both about its own axis and that of the knob, that the individual symbols or characters successively appear each in the same or upright position immediately in back of a window in the center of the knob.

Further in accordance with the invention, the drive for the dial is also within and concealed by the knob outline, so that all that is visible is the knob with its single dial reading. The elimination of distracting visible detail focuses attention of the observer upon the dial reading; this is particularly helpful when the controlled device, as in the case of Wheatstone bridges, potentiometers, multi-point switches, and the like, is provided with a plurality of control knobs whose settings must be frequently changed and read.

The invention further resides in features of construction, combination and arrangement hereinafter described and claimed.

For more detailed understanding of the invention, reference is made to the accompanying drawings, in which:

Fig. 1 is a perspective view of a control knob embodying the invention;

Fig. 2 is a sectional view on enlarged scale of the control knob of Fig. 1;

Fig. 3 is an exploded view showing components appearing in Fig. 2;

Fig. 4 is a sectional view on enlarged scale showing a difierent internal construction of the knob of Fig. 1; and

Fig. 5 is an exploded view showing parts appearing in Fig. 4.

In the usual control knob arrangement used for manipulation of switches, valves and the like, there is attached to it a dial having characters or face of the cone.

symbols, all concurrentl visible to an observer, which for diiferent settings of the knob are successively opposite a stationary index; alternatively, there may be attached to the control knob a pointer which for different settings of the knob is opposite various legends, symbols or markings, indicating the control setting. Such arrangements occupy considerable panel space, and in addition there is ever present the possibility an observer, because of haste or inexperience, will improperly read the setting.

Though the invention is not limited thereto, there are herein disclosed two control knobs of similar external appearance but of somewhat clifferent internal construction. As shown in Fig. 1, there is visible to the operator or observer a control knob l0 having a window or opening through which successivel appear numerals or other indicia uniquely identifying the setting of the knob. There is no external dial or pointer arrangement which would not only occupy much greater panel space but would create the possibility of confusion in reading of the knob settings.

The details of internal construction of one suitable dial and operating mechanism therefor is shown in Figs. 2 and 3. The knob shell I2, of size suitable to be conveniently grasped and manipulated by the operator, is hollow and its upper face, as viewed in Fig. 2, is provided with a central aperture or window H preferably closed for exclusion of dust by a pane 13 of transparent material, such as Celluloid or the like. The shell l2 may be of any suitable material, metallic or otherwise; for example, it may be of molded insulating material, particularly when used to control the setting of the shaft of electrical switches or contact members. To the ledge member I 4 suitably secured within the shell l2, or formed integrally therewith, is fastened, as by screws l5, a coupling bracket I6 suited to receive the shaft I! of a switch or other device to be controlled. A

set screw l8, or equivalent, is used to hold the control knob to the shaft ll. The dial member [9, in the specific arrangement shown in Figs. 2 and 3, is in the form of a truncated cone with the dial markings spaced angularly on the sur- The dial member I9 is mounted for rotation on the jack shaft 20 carried by, or integral with, the coupling bracket I6. The axis of the jack shaft 20 is inclined at such angle with respect to the axis of rotation of shaft I! that as the dial member I9 is rotated, the dial markings in turn appear beneath the window H.

Axial movement of the dial member along the driver or other tool for loosening; or tigh-tening of the set screw l8 which normally, holds. the knob assembly to the shaft W:

To effect rotation of the dial member. lmwith respect to the knob as the knob is turned about the axis of shaft I'!, there. is. provided a sta tionary gear member 24 which in the particular construction shown slipsover the shaft bushing 2 5 and is held against the front face of the panel 26 by the clampingnut 27 used'to holdthe bushing 25' in place. Additionally, to preventaccidental movement of the gear 24, it is provided with a locking tip 28, which maybe pressed out from the gear blank itself, received by a slotor opening 29 in the instrument panel 26.- Preferably, and as shown, the stationary gear 24, as well; as all of 'the other dial operating parts, are concealed within the knob so that the only movable part visible to the operator is that restricted portion of the dial member 19' visible through the window II,

The numerals or letters on thedial member l9 are, so p it o d atalthous he d a otat s both about its oWn axis, that is, the axis of. the jack shaft, 20, and the axis of the shaft 11, the successive markings or in jq a nevertheless al,- ways appear in the. sameposition withrespect to the observer. so clearly, to identify the particular circuit or circuit, element in use, or the particular setting of a valve or other controlled element. The central location of the wind'owin the domed face of the knob with the dial face immediately behind it provides an. unobstructed view, of: the

dial symbols andfor best visibility under existing light conditions.

In additionto the operating advanta es above mentioned, it shouldalso be noted. thattheknob may be used with, devices, already installed for use, in replacement of other. types, merely by clamping the gear 24v in place and putting, the knob, l0 onthe shaft I111; no aqqessto the reverse side of the panellor to the interior of the enclosure including it. is required.

Thevv control. knob. arrangement shown, in Figs. 4 and 5,15 generally similar t'pthat of'Figs. 2 .andf3, andaccordingly the corresponding parts are iden tified by the same reference characters. The main diffe e between the t o cons u iqn i that inthe modification of Eig s. 2. and the stationary gear 24 is held against the P 1 191 26 and, is not removable with the knob, L0 from th c o a t whereasi'n th mg ficat qn of Figs. 4 and, 5, the stationary driving gear 24A is-part of the knob. assembly detachable as a. unit fromthe controlled. shaft 1.1.. With the construction. of Fig. 4,. the proper clearance for smooth operation of gearszzfl and-[24A is adjusted; once and for all at the factory, whereas with the construction of Fig. 2,v the proper clearance must be. reestablished whenever, the knob, l2 has been, loosened on shaft [1,.

A modified. form of, dial. member and method 0t mounting it is also shown in Fig; 41. In this modification, the jack shaft A is separate from The hole 23 pro,-.

4 the coupling bracket ISA and is provided with a threaded end 30 received by the boss 3| of the bracket I 6A. The dial plate 32 on which the position-setting characters appear is separate from the body member 34 and is detachably held thereto by a plurality of screws 33: this type construction is of advantage. in, that to adapt the constructionfor various-usesit is only necessary to carry in stock differently marked inexpensive cones 32 rather than relatively expensive casting and gear assemblies 34-22. The twomembers-32 and 34 comprise dial member 19A.

Intheconstruction of Figs. 4 and 5, the lower end. of the coupling member IGA is of reduced diameter to. pass through the opening 36, Fig. 5, in the upper end of the cone-shaped member 35 towhich is secured the driving gear member 24A. The. member 31 which threadably engages the reduced end portion 38 of the coupling member LEA, cooperates therewith to provide a groove, in which the cone-shaped member 35'is free to rotate with. respectv to the knob It) as a whole. The cone member 35,, is. provided with a notch 39 which receives, when the knobis slipped in place on the control shaft I11, the locking tip 40 which is bent upwardly from the disc 41' clamped against thepanel ZB by, thenut 21. To prevent accidental rotation of the locking; plate 4 I it may be provided with the tips 28A bent downwardly therefrom and received by the slots. or openings 29 in the panel 26: the openings 29. are preferably at different distances. from. the axis of shaft, I11 so that there is only, oneposition of plate 4| for which the tips 28A. and openings 29 are in register. There is thus defined a single position at which the notchv 39. of gear-cone 35 will engage. the tongue 40 of. plate. 4.1. Thus, to insure proper correspondence betweenthe dial indications and the angular-positionsof shaft I'T, it is only necessary, inreplacing the control knob, tomakecertain. the set-screw l8. engages the usual depression or. flattened area, of. the shaft, and. the tongue 40 engages with the slot 39.

Asthe. knob Illisrotatedby thev operator tothe various control settings ofthe switch, or other member, actuatedbyshaft I], the dial member IBA rotates about the. axis. of-shaft l1, and. also because ofv the engagement between the. gears 12 and 24A rotates.- about its own axis, that is, the axis of thejack shaft 2,0A,.thus,in succession tomove the. various, dial. markings, into view through the window H. Aswith. the modif es..- tionof Figs. 2. and.3, all of. the.- driving mechanism of the dial is concealedwithintheknob, and there is visible. to the. observer onlythe marking. indicating the position, of the. associated device. or equipment. All other moving parts which would distract the. observer are hidden, and. are. within the knob; itself, so. affording, compactness not attainable with constructions usingexternal-dials and pointers. Furthermore, as. with the modification of Figs. 2 and 3, their-nob maybe installed, without any need. fps access ta the reverse. face of the panel 26.

It shall be understood. the: invention is. not limited to the particular arrangements speci fically disclosed and. that. changes and modificationsmay-be made within the scope of the; ap: pended claims.

Whatis claimed is:

1. An arrangement comprising. a hollow con trol knob. having. a window in its, face, a. conical dial member. having. indicia successively visible r u ha d indow. t uttu e for u rti said dial member within said knob for rotation therewith and for rotation about an axis inclined with respect to the axis of rotation of the knob, a driven member attached to and rotatable with said dial member, and a stationary driving member operatively engaging said driven member to effect rotation thereof about its said inclined axis as said knob is rotated about its own axis.

2. A hollow knob assembly detachable as a unit from a shaft to be controlled comprising a dial member rotatably mounted within said knob and having indicia successively visible through a window in the knob face, a gear rotatable with said dial member, and a second gear mounted within said knob concentric with its axis of rotation for driving engagement with the first gear and suited detachably to engage a locking member preventing its rotation when the knob is on said shaft.

3. A hollow knob assembly having a window around the central axis thereof, means for attaching said knob assembly to a shaft extending axially of said assembly, a dial member within said hollow knob, means supporting said dial member for rotation about an axis inclined to that of said knob assembly for rotation of said dial member past said window, and a driving connection effective upon rotation of said knob to move said dial member relative to said window.

4. An arrangement for effecting rotation of a rotatable shaft and indicating the position thereof comprising a hollow control knob having a window which is centrally located at the axis of rotation of the knob, means for securing said knob to said rotatable shaft, a dial member within said knob and having angularly spaced indicia, structure for supporting said dial member within said knob for rotation about its own axis and for rotation around the axis of the knob, and means including a stationary member having a driving connection with said dial member effective upon rotation of the knob and dial member about the axis of rotation of the knob to effect rotation of said dial member about its own axis successively to present said indicia to said central window of the knob.

ALBERT A. SEASONIGOOD.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 2,068,693 Newell et a1 Jan. 26, 1937 2,104,521 Jackson et al Jan. 4, 1938 2,119,576 Goldstine June '7, 1938 2,222,987 Perry Nov. 26, 1940 

